EP 0518285 B1 19941026 - Circuit for a volume flow measuring device used for a medium flowing in a pipe.
Title (en)
Circuit for a volume flow measuring device used for a medium flowing in a pipe.
Title (de)
Schaltungsanordnung für eine Vorrichtung zur Messung des Volumenstroms eines ein Rohr durchfliessenden Mediums.
Title (fr)
Circuit pour un dispositif de mesure du débit volumétrique d'un milieu en écoulement dans un tube.
Publication
Application
Priority
DE 4119372 A 19910612
Abstract (en)
[origin: EP0518285A1] The invention relates to a circuit arrangement for a volumetric flow-measuring device for a medium flowing in a pipe, which has two coils arranged on opposite sides of the pipe and at least one pair of electrodes which are arranged next to the inner surface of the pipe symmetrically with respect to a plane defined by the axis of the pipe and a common axis of the coils, having an excitation circuit for the coils which permits excitation of the coils in order to generate magnetic fields directed in the same and opposite senses, and having an evaluation circuit, connected to the electrodes, for deriving a measured value signal which is proportional to the volumetric flow of the medium, characterised in that the coils are assigned a clock-generator and phase-shifter arrangement for controlling a similar, although phase-shifted by 90 DEG , periodically bipolar excitation of the two coils, in that there is provided at the electrodes a holding circuit for separately fixing the signals emitted by the electrodes in a first holding element in the case of magnetic fields generated in the same sense in the one direction, in a second holding element in the case of magnetic fields generated in the same sense in the other direction, in a third holding element in the case of magnetic fields that are to be directed onto one another in opposite senses, and in a fourth holding element in the case of magnetic fields directed away from one another in opposite senses, in that a first summing circuit is provided for summing the signals held in the first holding element and in the second holding element in order to generate a first aggregate signal, in that a second summing circuit is provided for summing the signals held in the third holding element and in the fourth holding element in order to generate a second aggregate signal, and in that a correction circuit is provided in which the first aggregate signal is corrected using the second aggregate signal in order to generate the measured value signal. <IMAGE>
IPC 1-7
IPC 8 full level
CPC (source: EP US)
G01F 1/002 (2013.01 - EP US); G01F 1/60 (2013.01 - EP US)
Designated contracting state (EPC)
CH DE DK FR GB LI NL
DOCDB simple family (publication)
EP 0518285 A1 19921216; EP 0518285 B1 19941026; CA 2071296 A1 19921213; CA 2071296 C 20020423; DE 4119372 A1 19921217; DE 59200683 D1 19941201; DK 0518285 T3 19941205; JP 3147998 B2 20010319; JP H06341873 A 19941213; US 5299461 A 19940405
DOCDB simple family (application)
EP 92109735 A 19920610; CA 2071296 A 19920616; DE 4119372 A 19910612; DE 59200683 T 19920610; DK 92109735 T 19920610; JP 15369492 A 19920612; US 89561292 A 19920609